In the last chapter, we explored a powerful data organization concept in Cassandra—the compound primary key. This allowed us to construct a table for status updates that satisfies two important requirements: related data is grouped together, and records have a built-in ordering within each group. So far, however, we only have two tools for querying data: either retrieve a single row using its full primary key, or retrieve all the rows in a table. In this chapter, we will dive into the more sophisticated queries that are available on tables with clustering columns, and use these queries to build the main reading interface for our MyStatus application. By the end of this chapter, you'll know: